In order to control regional acid deposition pollution, it is necessary to determine scientific regional control targets for atmospheric acid deposition. This study proposed a method to conduct multi-site simulation using the VSD model and the simulation results were plotted by cumulative frequency distribution curves. Then the regional acid deposition control targets were determined based on the analysis of the restoration of the soil in the region under different deposition scenarios in the target years. The method was applied in the Guangzhou-Dongguan-Huizhou region. To analyze the control targets for acid deposition in this region, 25 sites were simulated by VSD model based on onsite soil sampling and investigation, and the results were plotted by cumulative frequency distribution curves. The results indicated that when S deposition was controlled alone and if the protection rate was 80%, the S control targets should be 7.68-12g.m-2.yr-1 in the short-term and 10.24-16g.m-2.yr-1 in the long-term; the short-term and long-term S deposition control targets should be 5.12-8g.m-2 .yr-1 和7.68-12g.m-2 .yr-1 if the protection rate was 95%. When the S and BC depositions were controlled simultaneously and if the protection rate was 80%, the S control targets should be 2.56-4 g.m-2 .yr-1 in the short-term and 5.12-8 g.m-2 .yr-1 in the long-term when BC deposition was 6.4-12.8 g.m-2 .yr -1 ; and the S control targets should be 2.56-4 g.m-2.yr-1 when BC deposition was 4.8-9.6 g.m-2.yr-1. If the protection rate was 95%, the S control targets should be 0.64-1 g.m-2.yr-1 in the short-term and 5.12-8 g.m-2.yr-1 in the long-term when BC deposition was 6.4-12.8 g.m-2.yr-1; and the S control targets should be 0.64-1g.m-2.yr-1 in the short-term and 2.56-4g.m-2.yr-1 in the long-term. When BC deposition was 2-4 g.m-2.yr-1, S deposition should be controlled to 0.64-1g.m-2.yr-1 for the protection rate of 80% and 95%, and some manual restoration measures are required at the same time

To estimate the biogenic volatile organic compound (BVOC) emissions in China, this study collected data on vegetation volume, production and distribution, converted into leaf biomass and then used BVOC emission model. In 2003, the annual BVOC emission in China was 12.83 Tg, composed of 7.45 Tg isoprene, 2.23 Tg monoterpenes, and 3.14 Tg other VOCs (OVOCs). Emissions varied significantly among plant species, with contributions ordered as follows: forests > shrubs > crops > grasslands. Southern and northeastern China were the main sources of BVOC emissions. Significant seasonal variation was found with summer contributing the most.

Multi-year inventories of anthropogenic black carbon emissions, including both fuel consumption and biomass open burning, at a high spatial resolution of 0.25°×0.25° have been constructed in China using GIS methodology for the period 1980–2009, based on official statistical data and time-varying emission factors. Results show that black carbon emissions increased from 0.87 Tg in 1980 to 1.88 Tg in 2009 with a peak in about 1995, and had been continually increasing in the first decade of the 21 century. Residential contribution to the total BC emissions declined from 82.03% in 1980 to 42.33% in 2009 at a continuous diminishing trend, but had always been the dominant contributor in China. While contributions from industry and transportation sectors had increased notably. BC emissions were mainly concentrated in the central eastern districts, the three northeastern provinces and the Sichuan Basin, covering 22.30% of China's territory, but were responsible for 43.02%, 50.47%, 50.69% and 54.30% of the national black carbon emissions in 1985, 1995, 2005 and 2009, respectively. Besides, China made up 70%–85% of BC emissions in East Asia, half of the emissions in Asia, and accounted for averagely 18.97% of the global BC emissions during the estimation period.

Visibility in the Sichuan Basin of China has long been at low levels due to topographic features and high pollution. This study produced trend maps tracking the spatial patterns and temporal trends of visibility in the Sichuan Basin based on 38 years of daily visibility data. Three major fluctuations in the visibility pattern were found: a period of decreasing visibility from 1973 to 1990, a period in which the visibility pattern remained stable from 1991 to 2000, and a period of the visibility recovery from 2001 to 2010. Data from 12 stations in the Sichuan Basin were further analyzed using cumulative percentiles, ridit analysis and days of visibility > 19 km and < 10 km. Hazy conditions were most prevalent in Chengdu and Chongqing, which had visibility less than 10 km and more than 200 low visibility days per year after 2000. Fengjie, Youyang and Langzhong showed consistent declines in visibility and in the number of days with visibility > 19 km whereas Liangping, Nanchong and Wanyuan experienced relatively small decreases but much variation. Upturn trends were observed in Daxian, Mianyang, Ya'an and Yibin after 1995. Although the specific trends differed among stations, a general trend of reduced visibility was found over Sichuan basin. Median visibilities in 2000s were approximately 4 to 38% lower than those during the 1970s, indicating that more efforts are needed for recovery. This study represents the first comprehensive analysis of long-term visibility patterns in the Sichuan Basin.